NEW YORK — People who pay high fees to borrow from so-called payday lenders generally don’t have bank accounts, but that doesn’t mean banks aren’t making money from them.

Major banks, led by Wells Fargo, US Bancorp and JPMorgan Chase, provide more than $2.5 billion in credit to large payday lenders, researchers at the Public Accountability Initiative estimated in a report released this week.

The financing provides vital support for an industry criticized for charging effective annual interest rates that can top 400 percent, the researchers said.

“Not having financing would shut the big players down,” said Kevin Connor, a co-author of the report and a director of the Public Accountability Initiative, a nonprofit research group that has been critical of big business.

Some major banks have shied away from doing business with payday lenders because of concerns about their practices or about the sector’s image.

“Certain banks have notified us and other companies in the cash advance and check cashing industries that they will no longer maintain bank accounts for these companies due to reputational risks and increased compliance costs,” Advance America, the biggest payday lender, wrote in a regulatory filing.

Citigroup, for example, says it doesn’t lend to the industry. Bank of America has financed some payday lenders but tries to avoid doing so, applying a stricter-than-usual screening process when they apply for credit, bank spokesman Jefferson George said.

“We have a limited appetite for doing business with them,” he said.

San Francisco-based Wells Fargo provided credit lines to six of the eight largest publicly traded payday lenders and also provided early financing to help the businesses expand, according to Tuesday’s report

A spokesman for Wells Fargo said the company sought to provide equal access to credit for all “responsible companies.”

“We exercise strict due diligence with payday lenders and check cashing companies to ensure that they, just like us, do business in a responsible way and meet the highest standards,” the spokesman, Gabriel Boehmer, said, adding that Wells applied stricter criteria to the industry.

“We put payday lenders through an additional level of scrutiny that other companies and industries might not have to go through,” he said.

A JPMorgan Chase spokesman declined to comment, while US Bancorp did not respond to a request for comment.

Payday lenders typically charge $15 in fees for each $100 borrowed, fees that are charged each time a loan is rolled over for two more weeks. The Center for Responsible Lending estimates the average effective annual interest rates on these loans is 417 percent.